• Journal of Korean Society of Coastal and Ocean Engineers
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• v.34 no.1
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• pp.11-18
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• 2022

In order to improve the accuracy of particle tracking prediction techniques near the Korean Strait, this study compared and analyzed a particle tracking model based on a seawater flow numerical model and a machine learning based on a particle tracking model using field observation data. The data used in the study were the surface drifter buoy movement trajectory data observed in the Korea Strait, prediction data by machine learning (linear regression, decision tree) using the tide and wind data from three observation stations (Gageo Island, Geoje Island, Gyoboncho), and prediciton data by numerical models (ROMS, MOHID). The above three data were compared through three error evaluation methods (Correlation Coefficient (CC), Root Mean Square Errors (RMSE), and Normalized Cumulative Lagrangian Separation (NCLS)). As a final result, the decision tree model had the best prediction accuracy in CC and RMSE, and the MOHID model had the best prediction results in NCLS.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.6
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• pp.557-565
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• 1984

The year-to-year fluctuations of seasonal variation of sea surface temperatures (SST) in the Korea Strait are studied based on monthly SST data for more than 50 years at Mitsushima ana Okinoshima in the strait. The frequency distribution of SST has two peaks at temperatures below and above the multi-year average, but that of SST anomalies has only one peak at the zero anomaly. More than $95\%$ of the anomalies are in the range of ${\pm}2^{\circ}C$. The harmonic constansts of seasonal SST variation vary from year to year. The standard deviations of annual means, annual amplitudes, ana semi-annual amplitudes are less than $1^{\circ}C$, and those of the annual ana semi-annual phases are about $5^{\circ}$ and less than $50^{\circ}$, respectively. The SST in the Korea Strait have a tendency to decrease their amplitudes as the annual means increase. Physical mechanisms responsible for the analyzed results are discussed in this paper.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.1
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• pp.36-45
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• 2017

In the present study, the storm waves at the Korean Straits of April, 2016 have been reproduced by the wave hindcasting, and then their characteristics were investigated. Before the wave hindcasting, the wave measurements at the Korean Straits were analyzed. The analysis showed that the waves at the Korean Straits were dominated by the Northeastern waves, same as those in the East Sea. Accordingly, the wave hindcasting was been carried out with the same condition in Ahn et al. (2016). In the numerical results, the maximum significant wave height at the Korean Straits was 5.06 m, and the corresponding significant wave period was 9.2 s. The computed significant wave heights and wave periods were overestimated by 4 cm and 0.8 s, respectively. After the wave hindcasting, the computed significant wave heights and peak periods were compared with the JONSWAP relationship. This comparison showed that the storm waves at the Korean Straits were close to wind waves, not swell.

• Animal Systematics, Evolution and Diversity
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• v.2 no.2
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• pp.67-78
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• 1986

한국해역에서 알려진 집게류는 12과 57종, 게류는 20과 183종이다. 집게류는 집게과 (Paguridae) (19종)와 넓적왼손집게 과 (Diogenidae) (12종) 의 종들이 많고 게류에서는 물맞이게 과 (Maidae) (33종) 의 종이 가장 asg고 다음이 바위게 과(Grapsidae) (29종), 부채게 과 (Xanthidae) (22종), 꽃게 과 (Portunidae) (16종) , 달랑게 과(Ocypodidae) (16종)의 순이다. 저자는 한국 해역을 동해, 대한해협, 제주도해역, 황해의 4구역으로 나누고, 집게류와 게류를 북방형, 온대형, 남방형의 3분지형으로 나누었다. 집게류의 경우 북방형 9종, 온대형 40종, 남방형 8종이고, 게류의 경우 북방형 7종, 온대형 87종, 남방형 89종이다. 집게류의 경우 동행 29종, 대한해협에 30종, 제주도해역에 30종, 황해에 21종이 게류의 경우 위의 순서대로 62종, 121 종, 104 종, 74종이 분포하며, 각 해역에서의 분포형도 고찰했다. 각 해역에만 분포하는 종의 수는 집게의 경우 동해에 8종, 대한해협에 3종, 제주도해역에 16종, 황해에 0종, 게류의 경우 위의 순서로 8종, 20종 40종, 12종이다. 집게류는 북방형종이, 게류는 남방형종이 비교적 많으며 동해에는 북방형종들이 제주도에는 남방형종들이 비교적 많다. 4구역 중 2 구역 (6조합) 사이의 유사계수(r=a/a+b+c)를 계산한 바 양 분류군 모두 대한 해협과 황해 사이의 유사성이 가장 크고 (집게류 ; 0.55, 게류 : 0.59), 제주도해역과 황해 사이의 유사성이 가장 적다. (집게류 ; 0.20, 게류 : 0.19). 분포상을 이해하기 위하여 각 해역의 환경조건도 알아보았는바, 분포의 양상과 해황과 잘 부합된다.

• Journal of the Korean earth science society
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• v.27 no.4
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• pp.464-474
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• 2006

The paleoceanography since 14 ka was reconstructed based on the planktic foraminiferal assemblages of core sediments from the outer shelf of the Korea Strait. Planktic foraminifera in the core sediments can be divided into four assemblages: A, B, C, and D. Assemblage A consists mainly of Globigerinoides ruber group and Globigerinoides conglobatus with low abundance (less than 10%), indicating the tropical-subtropical water mass. Assemblage B is composed of Pulleniatina obliquiloculata and Neogloboquadrina dutertrei, the indicator of Kuroshio Current, and shows the aspect of the inflow of the Tsushima Current into the Korea Strait. Assemblage C yields polar-subpolar species, mainly Neogloboquadrina incompta and N. pachyderma. It decreases upward of the core. Assemblage D contains coastal water species such as Globigerina bulloides and G. quinqueloba. It is abundant in the lower to middle region of the core. From the analysis of distributions of each assemblage and the result of age datings in the core, it is suggested that the Korea Strait played a role of channelling the East China Sea and the East Sea after the LGM (ca. 14 ka). During this time, the coastal water, affected by fresh waters originated from the river systems of China and/ or the Korean Peninsula, flourished around the Korea Strait and theses coastal water might entered to the East Sea. Around 8.5 ka, the effect of the Tsushima Current started to strengthen in this region, and the present current system seems to be formed at about $7{\sim}6ka$.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.2
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• pp.73-81
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• 2004

Voltage induced by the Tsushima Current on an abandoned submarine telephone cable has been measured since March 1998 in order to monitor the volume transport through the Korea Strait. Voltage has a good linear relationship with the transport measured by bottom-mounted Acoustic Doppler Current Profilers (ADCPs) along a section spanning the Korea Strait. This paper reviews researches using submarine cables briefly; we introduce the method to measure voltage on submarine cables, present some results focusing on the example of the Korea Strait, and mention the future prospect to use other submarine cables around Korea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.3
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• pp.208-215
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• 2000

The estimated total material transports through the Cheju Strait using all data which investigated in 1997 and 1999 are as follows; A large amount of suspended sediments and dissovted inorganic nutrients are carried tothe South Sea through the Cheju Strait by a persistent eastward flow (Cheju Current) from the Y311ow Sea andthe East China Sea. The annual material Oanspous by the Cheju Current are as follows; 22.9${\times}$10$^6$ ton yr$^{-1}$(SS), 0.52${\times}$10$^{10}$ mol yr$^{-1}$ (NH$_4\;^+$), 6.05${\times}$10$^{10}$ mol yr$^{-1}$ (NO$_3\;^-$), 0.36${\times}$10$^{10}$ mol yr$^{-1}$ (PO$_4\;^{3-}$), 10.27${\times}$10$^{10}$ mol yr$^{-1}$ (Si(OH)$_4$). The annual suspended sediment flux per water transport in the Cheju Strait (44.48${\times}$10$^6$ ton yr$^{-1}$ Sv$^{-1}$) is about 1.7 larger than that in the Korean Strait (26.08${\times}$10$^6$ ton yr$^{-1}$ Sv$^{-1}$). The annual nitrate flux per water transport (11.60${\times}$10$^{10}$ mol yr$^{-1}$ Sv$^{-1}$) is about 1.2 larger than that in the Korean Strait (9.72${\times}$10$^{10}$ mol yr$^{-1}$ Sv$^{-1}$) and 2/3 of that by Kuroshio in the East China Sea (18.55${\times}$10$^{10}$ ton yr$^{-1}$ Sv$^{-1}$). It suggests that chemical rich Cheju Current will play a significant role in the biogeochemical processes in the South Sea where the huge land-based waste are introduced.

• 한국해양학회지
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• v.7 no.1
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• pp.15-18
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• 1972

The observations of hourly change of salinity and temperature were made in the Korea Strait from August 1968 to July 1969. The largest hourly change of salinity and temperature was shown in August and the smallest in April. The range of hourly change of temperature (5.67-15.75$^{\circ}C$ on the depth of 125m) and salinity (32.1-34.3 on 20m layer) were significantly wide in August. These changes are correlated with the movement of water masses vertically and horizontally caused by changing direction and force of the current.

• Korea Petroleum Association Journal
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• s.284
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• pp.29-32
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• 2012

• Explosives and Blasting
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• v.9 no.3
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• pp.41-46
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• 1991